A Production BOM (Bill of Materials) lists the components required to produce one unit of a finished item. Business Central uses the BOM when refreshing a production order to calculate what materials need to be consumed. Without a certified BOM assigned to the item, production orders will have no component lines.
This guide covers creating a BOM from scratch, adding component lines, certifying it, and assigning it to an item card.
Production BOMs vs. Assembly BOMs
Business Central has two types of BOMs. A Production BOM is used with the Manufacturing module, it works with production orders, routings, and work centers. An Assembly BOM is used with the Assembly module for lighter, configure-to-order scenarios.
They are maintained in separate pages and are not interchangeable. This guide covers Production BOMs only.
Step 1: Open the Production BOM List
- Search for Production BOMs using
Alt + Q. - Select New to create a new BOM.
Step 2: Fill in the BOM Header
The BOM header identifies the BOM and sets the unit of measure it is defined against.
- Enter a value in the No. field. This is the BOM identifier, you can use an item number or a separate numbering series.
- Enter a Description for the BOM.
- Set the Unit of Measure Code. This should match the base unit of measure of the item you are producing. If you produce in pieces, set this to
PCSor the equivalent code in your system.
Leave the Status as New for now. You will certify the BOM after adding component lines.
Step 3: Add Component Lines
Component lines define each material required to produce one unit of the finished item.
- In the Lines section, select Item in the Type field for each standard component.
- Enter the No., this is the item number of the component.
- Set the Quantity per field to the amount of this component needed to produce one unit of the BOM item.
- Optionally, enter a Scrap % to account for expected material loss during production. Business Central adds this percentage on top of the base quantity when calculating component requirements on the production order.
- Repeat for each component.
The Type field on each line also accepts Production BOM, which is how you reference a sub-assembly (see Multi-Level BOMs below).
Step 4: Certify the BOM
A BOM must be in Certified status before it can be used on a production order.
- On the BOM header, change the Status field from New to Certified.
- Business Central validates the BOM lines before allowing certification. If any component item numbers are invalid or the BOM is incomplete, it will show an error.
If you need to edit a certified BOM later, you must first change the status back to New or Under Development, make your changes, then re-certify.
Step 5: Assign the BOM to an Item Card
Once the BOM is certified, assign it to the finished item.
- Search for Items using
Alt + Qand open the item card for your finished good. - Navigate to the Manufacturing tab (also called Replenishment in some versions, look for the Manufacturing FastTab).
- Set the Replenishment System to Prod. Order.
- Enter the BOM number in the Production BOM No. field.
- Close the item card.
When you create a production order for this item and run Refresh Production Order, Business Central will read the BOM and populate the component lines automatically.
Multi-Level BOMs
A multi-level BOM is one where a component is itself a produced item with its own BOM. For example, a finished bicycle might have a frame assembly as a component, and the frame assembly has its own BOM with individual parts.
To reference a sub-assembly in a BOM line:
- Set the Type on the BOM line to Production BOM.
- Enter the sub-assembly BOM number in the No. field.
When Business Central calculates material requirements for a multi-level production order, it can explode the BOM down through all levels. The depth of this explosion depends on your planning settings and the replenishment system set on the sub-assembly item.
Example BOM
Here is an example of a simple BOM for a wooden storage box:
| Line | Type | No. | Description | Quantity per | Scrap % |
|---|---|---|---|---|---|
| 10 | Item | WOOD-OAK | Oak Board 600mm | 2 | 5 |
| 20 | Item | NAIL-50MM | Nails 50mm | 24 | 0 |
| 30 | Item | HINGE-STD | Standard Hinge | 2 | 0 |
| 40 | Item | LATCH-01 | Box Latch | 1 | 0 |
The 5% scrap on the oak board means Business Central will calculate 2.1 boards as the required quantity on the production order component line, accounting for expected waste.
Once your BOMs are set up, the next piece of the production setup is defining how items are produced, the operations, machines, and time involved.
Learn how to configure operations in How to Set Up Routings and Work Centers in Business Central.